So what factors are causing the sinking? The study offers several suggestions but most notably, the scientists think dewatering, or draining flooded places, and groundwater pumping are most to blame.

They hope their study can help inform policy makers who work to protect the people of New Orleans. Lead author Cathleen Jones of NASA said, “Agencies can use these data to more effectively implement actions to remediate and reverse the effects of subsidence, improving the long-term coastal resiliency and sustainability of New Orleans. The more recent land elevation change rates from this study will be used to inform flood modeling and response strategies, improving public safety.”